Cutting device



Filed NOV. 13, 1967 ELL, JR 3,484,940

CUTTING DEVICE 2 Sheets$heet l INVENTOR. CHARLES C. ZELLJD! AGENT Dec.23, 1969 c. c. ZELL, JR 3,434,940

CUTTING DEVICE Filed Nov. 13, 1967 2 Sheets-Sheet 2 INVENTOR, -C//4R4 55c. 2&2) J

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United States Patent 3,484,940 CUTTING DEVICE Charles C. Zell, Jr., LosAlamitos, Califi, assignor to North American Rockwell Corporation FiledNov. 13, 1967, Ser. No. 682,488 Int. Cl. B261) 1/08, 4/48; A6lb 17/32US. Cl. 30--162 1 Claim ABSTRACT OF THE DISCLOSURE The inventiondescribed herein was made in the performance of work under a NASAcontract, and is subject to the provisions of the National Aeronauticsand Space Act of 1958, Public Law 85-568 (72 Stat. 426; 42 U.S.C. 2451)as amended.

Background In the manufacture of large complex electronic equipment,numerous wires are used to interconnect various points of electroniccircuitry; these wires traversing many tortuous paths in order toterminate at desired places. It had been the practice, in so-calledin-place wiring, to affix one end of the wire at its desired point;route the wire over a selected path; and to then aifix the other end ofthe wire to its designated location. As wires were sequentiallypositioned in this way, it was found that various wires tended to haveparallel adjacent paths; and it became the practice to cable these wiresinto a bundle; that is, to lace the wires together with suitablelacing-cord. This cabling provided a neater appearance, and-in manycasesa more rigid arrangement wherein the wires would not move whensubjected to vibration or shock.

It was soon discovered that economies could be achieved if these wireswere sub-assembled; that is, cabled together externally of theapparatus, to form a wire-harnessand the wire-harness then just droppedinto place in the apparatus. If the wire-harness had been properly made,the ends of the various wires were automatically positioned at, or near,their desired terminating points.

As wire-harnesses became evermore larger and complex, it becamenecessary to temporarily bundle some wires, in order to provide acompact arrangement that permitted additional wires to be added.Therefore, temporary ties were used to form temporary cables; the stringforming the temporary ties being cut and replaced by new ties thatencompass additional wires as the wire-harness increased in size. Atother times, a series of ties had to be cut away in order to add,remove, or repair a wire.

It was soon found, that-regardless of the operators skill, experience,and care-the devices used for cutting the temporary ties frequentlyslipped; and nicked or actually cut one or more of the wires in thewire-harness. The nicked or cut wires required repair; or even worse, ifnot corrected, caused a malfunction of the equipment that showed up muchlaterafter virtual completion of the apparatus. In an attempt tominimize harming the wires, many cutting implements were tried; theseincluded ordinary knives and scissors, surgical scissors havingprotected points, seam-rippers, and other devices. Unfortunately, noneof these cutting devices proved completely satisfactory.

3,484,940 Patented Dec. 23, 1969 Objects and drawings;

It is therefore an object of the present invention to provide animproved cutting device. The attainment of this object and others willbe realized from the following detailed description; taken inconjunction with the drawings of which FIGURE 1 illustrates oneembodiment of the invention;

FIGURE 2 illustrates an opened-up view of said embodiment;

FIGURE 3 illustrates a second embodiment; and

FIGURE 4 illustrates still another embodiment.

Synopsis Broadly speaking, the present patent application discloses acutting tool wherein the cutting-element is nor mally sheathed; so thatthe cutting-edge remains hidden until it is intentionally brought intocontact with a material to be cut. The various embodiments disclose anexternal hook for properly positioning the cutter; slots and/orapertures for positioning the material to be cut; a finger-hole forholding the cutter in a convenient, yet non-interfering position duringordinary work; clips for supporting the tool during non-use intervals,etc.

Description FIGURE 1 shows an embodiment that is specifically designedfor cutting the ties of a wire-harness. As shown, cutter 10 is a handheld manually-operated device, comprising a housing 12--a portionthereof acting as a sheath for a cutting-element 14 having acutting-edge 16. FIG- URE 1 shows cutting-element 14 partially advancedso that cutting-edge 16 is unsheathed. Normally-during non-useintervals-cutting-element 14 is retracted, as by means of a biasingspring, so that its cutting-edge 16 is sheathed; and cannot accidentallycut any of the wires.

In use, an elongated partially tapered hook 18 is engaged with the tie20 to be cut. Hook 18 and housing 12 are configurated to form a narrowinlet 22 that communicates with a reentrant formation of thehook-housing to produce a cutting-aperture 24. Thus, the tie 20 to becut slides through narrow inlet 22 into a suitably-shapedcutting-aperture 24. In order to cut the tie, a thumb-button 26 which isattached to cutting-element 14, is manually moved forward. Thisoperation advances cutting-element 14, so that its cutting-edge 16 isunsheathed, as shown, and makes contact with tie 20. Due to the shape ofthe cutting aperture 24 and the angle of the cutting-edge 16, theforward movement causes cutting-edge 16 to slice across tie 20; and tothus cut it in a smooth efficient manner.

It will be noted that during the cutting operation, only the tie 20 isin contact with the cutting-edge 16. The wires of the harness, beingperpendicular to tie 20, are not engaged by the cutting-edge 16; andmoreover, the inlet 22 between book 18 and the body of housing 12 is sosmall that only the tie, and not the wire can enter. In this way, thedisclosed cutter safely cuts the tie, without endangering or cutting thewires themselvesand does not expose the tie to any strain or pull thatmight cause it to cut into the wires insulation. Moreover, a finger-holepermits the operator to hold the cutting-device in a convenient, and yetnon-interfering manner duringand between--cutting operations.

Ordinarily the tie to be cut has been tied fairly snugly 3 tie 20, andthe housing rocked upwards in such a manner that fulcrum-portion 25causes the hook-tip to tens1on the tie, and thus permit the now-loosenedtie to slide along inlet 22 into cutting-aperture 24.

The embodiment of FIGURE 1 is shown in a disassembled form in FIGURE 2.Housing 12 comprises two substantially mirror-image parts 12a and 12b;and cuttingelement 14 is positioned in a blade-holder 30, whose rearendhas a spring-pin 31 engaged by one end of an extension-spring 32 havingits other end afiixed to an anchoring pin 3-4. Thus, spring 32 normallyretracts cuttingelement 14 so that its cutting-edge 16 is safelysheathedas illustrated.

Each housing-half, 12a and 1212 has suitable recesses to receive blade14, blade-holder 30, spring 32, and anchoring pin 34; the forwardportion 36 of the recess being suitably sized and shaped to act as aslide-guide for blade 14. In the embodiment shown, one housing portion-12b in this casehas threaded holes 38 for accepting screws 40 that holdtogether the two parts of the housing; the other housing-portion, 12a,having countersunk clearance-holes for positioning the holding screws40. Alternatively, a plastic housing may have threaded inserts; or maybe permanently bonded together.

As shown, blade-holder 30 has a blade-pin 33 for accepting the hole ofblade 16, and has a threaded hole 35 for receiving the threaded shaft ofthumb-button 26; and each housing-half has a suitable slot 42 forclearing the shaft of thumb-button 26, which may therefore be screwedinto the blade-holder 30 from either side. Thus, thumb-button 26 mayproject from either side of the housing, in order to facilitate use byeither right-handed or left-handed operators.

In order to prevent the tip of the blade from pressing against thehousing, its forward motion is stopped by the abutting of the end of thethumb-button shaft against the end of its clearance slot, 42, or by theabutting of bladeholder 30 against the end of its guide-slot.

The housing shown in FIGURES 1 and 2 has a hook portion 18 at an angleof about relative to the longitudinal axis of the housing; this angularrelation permitting easy insertion of the hook-tip under the tie to becut, and still permitting sufiicient clearance for the hand of theoperator to be positioned above the wire-harness. It will be noted thathook 18 and housing 12 co-act to form the relatively narrow opening orinlet 22 between the hook 18 and the body of the housing; this inletbeing suitably proportioned and narrow so that only the tie, and not thewire, will be admitted into the cutting-aperture 24. Where desired, themovement of the blade may be such as to close the inlet, and to thusprevent the introduction of additional material into thecuttingaperture.

It has been found that if cutting-aperture 24 has a suitable shape, theadvancement of cutting-edge 16 traps the tie at a corner of thecutting-aperture; and then slices cleanly across the tiethus producingan efiicient, clean, cutting action.

Alternatively, a compression spring may be used to bias the knife-edgeto a normally advanced and sheathed position. In this case, the cuttingaction is produced by (1) retracting the blade, (2) admitting the tieinto the cutting aperture; and (3) then advancing the blade for thecutting operation. 7

A somewhat ditferent arrangement is shown in FIG- URE 3. Here acompression-spring 48 abuts one end of blade-holder 50; and a trigger 52has a pin 54 that passes through a suitable guide-slot in the housing,and through a hole 59 in the blade 56. In operation, trigger 54 ispulled back to compress spring 48 and is then releasedwhereupon thecompressed spring drives the blade forward for the desired cuttingaction. If desired, trigger 52 may be designed and mounted to projectupwards, downwards, or to either side.

As discussed previously, in order to prevent blade-tip pressure on thehousing, the end of the guide slot acts as a stop for the trigger-pin;or else the slide-recess acts as a stop for blade-holder 50.

FIGURE 4 shows another embodiment, this comprising a housing that takesthe form of a tube 60; suitable endplugs 62 being used to close thetube. A cutting-blade 64, having a width substantially equal to theinside diameter of the tube, is positioned within the tubeso that theinner surface of the tube acts as the sliding-guide. Thumbbuttons 66,fitting through longitudinal slots 68 and a hole in blade 64, preventthe blade from turning; and provide means for advancing the cutting-edgepast cutting-aperture 70. In this embodiment, no blade-holder is used.This particular embodiment is illustrated as being entirely manual,dispensing with the previously-used biassing springs; and, if desired, apencil-type clip instead of a finger hole.

In production processes other than cabling wire, bundles of material aretied in a similar manner; except that due to their weight, a tie ofwire-rather than string-may be used. The cutter described in connectionwith FIGURE 3 can be readily modified for cutting these tie-wires; themodification involving the following changes. In order to cut thetie-wire, a slicing action is not particularly desirable; and should bereplaced by either a shearing or pinching arrangement. For shearingpurposes, a flattened cutting-edge is forced to pass closely against afirmly-fixed shear edge, to produce a shearing action of thescissortype. For a pinching mode of operation, a tapered cutting edge isforced against a tapered die, in the manner of the well-knowndiagonal-cutter. In these embodiments, it is desirable to use a storedforce, rather than thumb pressure; and the spring and trigger mechanismof FIGURE 3 may be advantageously used-the spring force driving the edgeof the cutter against the wire and the backup shear or die.

It will be noted that the disclosed arrangements are such that thecutting-edge, the material to be cut, and the users fingers are alwaysprotectedboth while the cutting-edge is fully, or only partiallysheathed.

Although the invention has been described and illustrated in detail, itis to be clearly understood that the same is by way of illustration andexample only, and is not to be taken by way of limitation; the spiritand scope of this invention being limited only by the terms of theappended claim.

What is claimed is:

1. A cutting device for cutting a wire-tie surrounding a bundle ofwires, without cutting any of the wires, comprising:

a housing having a hook, a cutting-aperture, shaped to trap saidwire-tie for cutting said wire-tie, and sheath means for sheathing acutting-element, said cuttingaperture communicating with said sheathmeans, and the free end of said hook overlying a portion of said housingto coact therewith to form a narrow inlet that is suitably sized toadmit a tie to be cut, and to exclude wires to be protected from beingcut, said narrow inlet communicating with said cutting-aperture;

a cutting-element having a slicing-edge movably positioned in saidhousing;

means for guiding said slicing-edge of said cutting-element into and outof said cutting aperture and said sheath means-whereby said sheathedslicing-edge is protected from contact with all materials except thosewire-ties capable of passing into said cuttingaperture, and thesewire-ties may be contacted and cut by forward movement of saidslicing-edge of said cutting-element;

biassing means, positioned in said housing, for retracting theslicing-edge into a normally sheathed position; and

means, comprising a finger-button affixed to said cuttingelement, forovercoming said normally sheathed state, and manually advancing saidslicing-edge into said cutting-aperture in a slicing manner.

References Cited UNITED STATES PATENTS 896,117 8/1908 Jones 30-13 X2,198,111 4/1940 Gorbatenko et a1 30-162 2,541,063 2/1951 Hubbard 30-184X 6 2,615,181 10/1952 McGaughey 30-182 X 2,674,083 4/1954 Lezzeni 30-182X 2,722,740 11/1955 Hubbard 30-241 X GIL WEIDENFELD, Primary ExaminerUS. Cl. X.R.

